Write a (kindof) proper init, at least with the capabilities we have right now

apps/init.asm

@@ -1,24 +1,65 @@
 section .text
 global _start
 _start:
-    mov rax, 1
-    int 42h ; sys_yield
-    mov rdi, HelloLabel
-    mov rsi, 17
-    mov rax, 3
-    int 42h ; sys_write
-    mov rdi, 4000
+    mov rdi, welcome_label
+    call print
+    call next_line
+    mov rdi, 1000
+    call sleep
+    mov rdi, version_label
+    call print
+    call next_line
+    mov rdi, 2000
+    call sleep
+    mov rdi, end_label
+    call print
+    call exit
+
+sleep:
     mov rax, 2
-    int 42h ; sys_sleep
-    mov rdi, ExitLabel
-    mov rsi, 26
+    int 42h
+    ret
+
+strlen:
+    push rbx
+    push rcx
+    mov rbx, rdi
+    xor al, al
+    mov rcx, 0xffffffff
+    repne scasb
+    sub rdi, rbx
+    mov rax, rdi
+    pop rcx
+    pop rbx
+    dec rax
+    ret     
+
+print: ; string: rdi
+    push rdi
+    call strlen
+    mov rsi, rax
     mov rax, 3
-    int 42h ; sys_write
+    pop rdi
+    int 42h
+    ret
+
+next_line:
+    mov rdi, newline
+    mov rsi, 1
+    mov rax, 3
+    int 42h
+    ret
+
+exit:
     mov rax, 0
-    int 42h ; sys_exit
+    int 42h
 
 section .rodata
-HelloLabel:
-    db "Hello from init!", 0xA
-ExitLabel:
-    db "Well, bye. (init exiting)", 0xA
+version_label:
+    db "You are running Luna version v0.7-beta", 0xA, 0
+welcome_label:
+    db "Welcome to Luna!", 0xA, 0
+end_label:
+    db "Press any key to restart.", 0xA, 0
+newline:
+    db 0xA